While you probably love robots since you’re reading the Hackster blog, there’s a good chance that you also enjoy making music. As seen in the video below, James Bruton is definitely a fan of both, and he’s come up with a unique equalizer setup using — what else? — lasers!
His machine takes in audio signals via an MSGEQ7 graphic equalizer, which passes seven frequency readings on to an Arduino Mega. Dots from seven laser pointers that power the machine are turned into lines using a spinning mirror assembly, but in order to make the height of the lines proportional to actual sound, a few other tricks were needed.
Bruton considered carefully timing pulses from each laser to the angle of the spinning mirror segments, but notes that this would be quite difficult to do, as it would require a lot of processing speed, and the lasers may not even be capable of being switched that fast. He instead took a different — and perhaps obvious in hindsight — path, implementing seven servo-actuated shutters to intercept the laser beams a the correct height.
The resulting build appears to work well as a VU meter, and is quite the contraption itself. As Bruton notes in his video, be sure to wear the proper safety equipment when doing this kind of experiment!